Expanded Endoscopic Endonasal Approach Research Articles

Endoscopic pedicled nasoseptal flap reconstruction for pediatric skull base defects

A prospective study of endoscopic expanded endonasal approaches (EEA) with nasoseptal flap reconstructions revealed anecdotal evidence of less available relative septal length in pediatric patients. Our goal is to use radioanatomic analysis of computed tomography (CT) scans to determine limitations of the nasoseptal flap in pediatric skull base reconstruction and to describe clinical outcomes after using the nasoseptal flap in six pediatric patients. Six pediatric patients who underwent EEA with nasoseptal flap reconstruction were prospectively analyzed for flap coverage and postoperative cerebrospinal fluid (CSF) leak. Fifty maxillofacial CTs of individuals <18 years of age and 10 adult images underwent radioanatomic analysis. Measurements included potential nasoseptal flap dimensions and dimensions required to reconstruct an anterior skull base defect, a trans-sellar defect, and a transclival defect. Measurements were compared to determine if flap size would be sufficient to cover independent EEA defects within different age groups. Two out of three patients <14 years of age had inadequate flap coverage; one had a postoperative CSF leak. Patients >14 years of age had adequate flap coverage. Average potential flap length is less than average anterior skull base length until age 9 years to 10 years, and less than average trans-sellar defect length until age 6 years to 7 years. Septal growth is most rapid between 10 years and 13 years. : The pedicled nasoseptal flap may not be a viable option for EEA reconstruction in children <10 years of age. This flap is a reliable option in patients >14 years of age, as their septums are comparable to adults. Patients 10 years to 13 years of age require careful consideration of facial analysis and preoperative radioanatomic evaluation on an individual basis. Laryngoscope, 2009.

Clinical Outcomes Using the Expanded Endoscopic Endonasal Approach for Resection of Skull Base Chondrosarcomas

Clinical Outcomes Using the Expanded Endoscopic Endonasal Approach for Resection of Skull Base Chondrosarcomas

Defining the nasopalatine line: The limit for endonasal surgery of the spine

The expanded endoscopic endonasal approach (EEA) to the odontoid process is performed for decompression of the brainstem and to access tumors at the foramen magnum. Caudal exposure is limited by the nasal bones anteriorly and the hard palate posteriorly. We define the line connecting these two points as the nasopalatine line (NPL) and the nasopalatine angle (NPA) as the angle between the nasopalatine line and the plane of the hard palate. This study was a retrospective cohort study. Pre and post-operative computed tomographic (CT) scans of 17 patients who underwent transodontoid EEA were reviewed. The position of the odontoid and the inferior extent of the tumor and surgical dissection were compared to the NPL. Factors affecting the posterior projection of the NPL, including basilar invagination and head position, were examined. The mean NPA was 27.1 degrees (range 21-31 degrees ). The NPL intersects the spinal column at 8.9 mm (range -9.0-8.7 mm) above the base of the C2 body. The base of the odontoid process and the inferior extent of surgical dissection were always above this line. Both basilar invagination and head position affect the relative position of the NPL. Patients with basilar invagination demonstrated a significantly lower posterior projection of the NPL than those without (P < .01). Maximal cervical flexion afforded more caudal exposure than cervical extension. The NPL accurately predicts the most inferior extent of surgical dissection. Further caudal dissection may require the use of angled instruments or a transoral approach.

Surgery for clival lesions: open resection versus the expanded endoscopic endonasal approach

Clival lesions pose significant challenges with regard to their surgical management. The expanded endoscopic endonasal (EEE) approach is a promising minimally invasive technique for lesions of the central skull base. The authors' aim in the current paper was to discuss the surgical treatment of clival lesions and to present the technical details, indications, and limitations of the EEE approach. Data from a recent endoscopically treated group will be compared with findings in a previous cohort of patients treated via classic open anterior and lateral approaches. Since June 2005, 17 patients with clival lesions underwent surgery via the EEE approach. Suitable candidates were chosen according to lesion characteristics, clinical parameters, and surgical goals. Neurological outcomes, Karnofsky Performance Scale scores, the extent of lesion resection, and complications were evaluated among these patients. Eighteen percent of the patients in the endoscopic group presented with recurrent disease. Another series of 43 patients, who had undergone resection of clival lesions via an anterior (rhinotomy, maxillectomy, microscopic transsphenoidal surgery, or transoral surgery) or lateral (pterional, frontoorbitozygomatic, or combined suprainfratentorial retrosigmoid) approach, was similarly reviewed. Twenty-three of these patients (53%) presented with recurrent disease and thus had undergone prior surgery. Following the EEE approach, 11 (79%) of 14 patients who had presented with neurological symptoms experienced improvement, and gross-total resection was achieved in 59% of the patients and subtotal removal in 41%. Complications included CSF leakage (24%), tension pneumocephalus (6%), and intracranial hematoma (6%). The patient with the latter complication was the only one who experienced permanent neurological worsening. In the open resection group, neurological worsening occurred in 33% of the patients (14 of 43). Total and grosstotal removals were achieved in 84% of patients and subtotal removal in 14%. The EEE approach has been shown to be a safe and effective technique for the resection of clival lesions with limited lateral extension. The choice of surgical approach must be tailored according to both patient and tumor characteristics. Although the 2 patient series featured in this paper are not comparable-because of a selection bias-higher rates of neurological morbidity and total and gross-total resections were observed in the open resection group. Given the long survival of some patients, the EEE approach should be favored whenever reasonable.

Palatal Flap Modifications Allow Pedicled Reconstruction of the Skull Base

Defects after endoscopic expanded endonasal approaches (EEA) to the skull base, have exposed limitations of traditional reconstructive techniques. The ability to adequately reconstruct these defects has lagged behind the ability to approach/resect lesions at the skull base. The posteriorly pedicled nasoseptal flap is our primary reconstructive option; however, prior surgery or tumors can preclude its use. We focused on the branches of the internal maxillary artery, to develop novel pedicled flaps, to facilitate the reconstruction of defects encountered after skull base expanded endonasal approaches. Feasibility. We reviewed radiology images with attention to the pterygopalatine fossa and the descending palatine vessels (DPV), which supply the palate. Using cadaver dissections, we investigated the feasibility of transposing the standard mucoperiosteal palatal flap into the nasal cavity and mobilizing the DPV for pedicled skull base reconstruction. We transposed the palate mucoperiosteum into the nasal cavity through limited enlargement of a single greater palatine foramen. Our method preserves the integrity of the nasal floor mucosa, and mobilizes the DPV from the greater palatine foramen to their origin in the pterygopalatine fossa. Radiological measurements and cadevaric dissections suggest that the transposed, pedicled palatal flap (the Oliver pedicled palatal flap) could be used to reconstruct defects of the planum, sella, and clivus. Our novel modifications to the island palatal flap yield a large (12-18 cm(2)) mucoperiosteal flap based on a approximately 3 cm pedicle. The Oliver pedicled palatal flap shows potential for nasal cavity and skull base reconstruction (see video, available online only).

Defining the Nasopalatine Line: Anatomic Limitations for Endoscopic Endonasal Surgery of the Odontoid Process and Upper Cervical Spine

Introduction: The expanded endoscopic endonasal approach (EEA) to the odontoid process is performed for brainstem decompression and access to foramen magnum tumors. Caudal exposure is limited by the inferior aspect of the nasal bones and the posterior hard palate. We define the line connecting these two points as the nasopalatine line (NPL); the nasopalatine angle (NPA) is the angle between the NPL and the hard palate.

Prospective Evaluation of the Nasoseptal Flap for Endoscopic Reconstruction of High Flow Intraoperative CSF Leaks during Endoscopic Skull Base Surgery

Introduction: Over the past 10 years, significant anatomic, technical, and instrumentation advances have facilitated the exposure and resection of intradural lesions via a fully endoscopic expanded endonasal approach (EEA). The vascularized nasoseptal flap (based on the posterior nasoseptal artery) has become our primary endoscopic reconstructive technique. The goals of this study are to prospectively evaluate the nasoseptal flap and high-risk CSF leak variables.

Outcomes following endoscopic, expanded endonasal resection of suprasellar craniopharyngiomas: a case series

Craniopharyngiomas are challenging tumors that most frequently occur in the sellar or suprasellar regions. Microscopic transsphenoidal resections with various extensions and variations have been performed with good results. The addition of the endoscope as well as the further expansion of the standard and extended transsphenoidal approaches has not been well evaluated for the treatment of this pathological entity. The authors performed a retrospective review of all patients who underwent a purely endoscopic, expanded endonasal approach (EEA) for the resection of craniopharyngiomas at their institution between June 1999 and February 2006. Endocrine and ophthalmological outcomes, extent of resection, and complications were evaluated. Sixteen patients underwent endoscopic EEA for the resection of craniopharyngiomas. Five patients (31%) presented with recurrent disease. Complete resection was planned in 11 of the 16 patients. Three elderly patients with vision loss underwent planned debulking, 1 patient with vision loss and a moderate-sized tumor had express wishes for debulking, and 1 patient had a separate, third ventricular nodule that was not resected. Of those in whom complete resection was planned, 91% underwent near-total (2/11) or gross-total (8/11) resection. No patient who underwent gross-total resection suffered a recurrence. The mean follow-up period was 34 months. Of the 14 patients who presented with vision loss, 93% had improvement or complete recovery and 1 patient's condition remained stable. No patient experienced visual worsening. Eighteen percent of patients (without preexisting hypopituitarism) developed panhypopituitarism and 8% developed permanent diabetes insipidus. There were no cases of new obesity. The postoperative cerebrospinal fluid leak rate was 58%. All leaks were resolved, and there were no cases of bacterial meningitis. There was 1 vascular injury (posterior cerebral artery perforator branch) resulting in the only new neurological deficit. No patient died. Endoscopic EEA for the resection of craniopharyngiomas provides acceptable results and holds the potential to improve outcomes.

Expanded endonasal approach, a fully endoscopic transnasal approach for the resection of midline suprasellar craniopharyngiomas: a new classification based on the infundibulum

Craniopharyngiomas are notoriously difficult to treat. Surgeons must weigh the risks of aggressive resection against the long-term challenges of recurrence. Because of their parasellar location, often extending well beyond the sella, these tumors challenge vision and pituitary and hypothalamic function. New techniques are needed to improve outcomes in patients with these tumors while decreasing treatment morbidity. An endoscopic expanded endonasal approach (EEA) is one such technique that warrants understanding and evaluation. The authors explain the techniques and approach used for the endoscopic endonasal resection of suprasellar craniopharyngiomas and introduce a tumor classification scheme. The techniques and approach used for the endoscopic, endonasal resection of suprasellar craniopharyngiomas is explained, including the introduction of a tumor classification scheme. This scheme is helpful for understanding both the appropriate expanded approach as well as relevant involved anatomy. The classification scheme divides tumors according to their suprasellar extension: Type I is preinfundibular; Type II is transinfundibular (extending into the stalk); Type III is retroinfundibular, extending behind the gland and stalk, and has 2 subdivisions (IIIa, extending into the third ventricle; and IIIb, extending into the interpeduncular cistern); and Type IV is isolated to the third ventricle and/or optic recess and is not accessible via an endonasal approach. The endoscopic EEA requires a thorough understanding of both sinus and skull base anatomy. Moreover, in its application for craniopharyngiomas, an understanding of tumor growth and extension with respect to the optic chiasm and infundibulum is critical to safely approach the lesion via an endonasal route.

Transpterygoid Transposition of a Temporoparietal Fascia Flap: A New Method for Skull Base Reconstruction after Endoscopic Expanded Endonasal Approaches

Endoscopic expanded endonasal approaches (EEAs) for the resection of lesions of the anterior and ventral skull base can create large defects that present a significant risk of postoperative cerebrospinal fluid (CSF) leak. These defects, especially in patients who received preoperative radiotherapy, are best reconstructed with vascularized tissue. The Hadad-Bassagasteguy flap, a pedicled nasoseptal flap, is our preferred method for reconstruction. This option is not available, however, in patients who underwent a previous posterior septectomy or in those with tumors that invade the pterygopalatine fossa (PPF) or sphenoid sinus rostrum. In this scenario, we have used a temporoparietal fascial flap (TPFF) for the reconstruction of large surgical defects. We developed a new technique for the transposition of the TPFF into the nasal cavity to reconstruct skull base defects after EEA. The flap is harvested using a conventional hemicoronal incision but is then advanced to the defect using a temporal-infratemporal tunnel and an endonasal transpterygoid approach. The latter is created using an endoscopic endonasal approach that involves the resection of the posterior wall of the antrum, dissection of the PPF, and partial resection of the pterygoid plates. These maneuvers open a bone window to accommodate the flap. The soft tissue tunnel, extending from the temporal to the infratemporal and then to the PPF, is opened with percutaneous tracheostomy dilators. We present a detailed description of the surgical technique and a retrospective review of two cases in which we used this technique. Two patients with large CSF fistulas who had undergone preoperative radiotherapy were reconstructed transposing the TPFF through a transpterygoid tunnel. We obtained an adequate exposure for placing the flap endonasally, and the flap provided complete coverage of the skull base defect. Both CSF leaks were resolved without any additional morbidity from the flap or the access technique. The TPFF is a reliable and versatile method for the reconstruction of the anterior, middle, clival, and parasellar skull base after EEAs. Its harvesting requires an external incision; thus, it is not our preferred method of reconstruction. It is recommended for large dural defects in patients with previous posterior septectomy and previous radiation treatment.

Expanded Endoscopic-Endonasal Approach to Nonpituitary Skull Base Lesions: One-Year Surgical Experience in 22 Consecutive Cases

Expanded Endoscopic-Endonasal Approach to Nonpituitary Skull Base Lesions: One-Year Surgical Experience in 22 Consecutive Cases

Endoscopic Expanded Endonasal Approach for Anterior Skull Base Lesions

Background: Endoscopic expanded endonasal approaches (EEAs) are used for the management of skull base lesions beyond the sella turcica.

Transpterygoid Transposition of a Temporoparietal Fascia Flap

Background: Endoscopic expanded endonasal approaches (EEAs) for the resection of lesions of the anterior and ventral skull base can create large defects that present a significant risk of postoperative cerebrospinal fluid (CSF) leak. These defects, especially in patients who receive perioperative radiotherapy, are best reconstructed with vascularized tissue.

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chondrosarcomas

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chondrosarcomas

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chordomas

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chordomas

Expanded Endoscopic-Endonasal Approach to Nonpituitary Skull Base Lesions: One-Year Surgical Experience in 22 Consecutive Cases

Expanded Endoscopic-Endonasal Approach to Nonpituitary Skull Base Lesions: One-Year Surgical Experience in 22 Consecutive Cases

A Novel Reconstructive Technique After Endoscopic Expanded Endonasal Approaches: Vascular Pedicle Nasoseptal Flap

In patients with large dural defects of the anterior and ventral skull base after endonasal skull base surgery, there is a significant risk of a postoperative cerebrospinal fluid leak after reconstruction. Reconstruction with vascularized tissue is desirable to facilitate rapid healing, especially in irradiated patients. We developed a neurovascular pedicled flap of the nasal septum mucoperiosteum and mucoperichondrium based on the nasoseptal artery, a branch of the posterior septal artery (Hadad-Bassagasteguy flap [HBF]). A retrospective review of patients undergoing endonasal skull base surgery at the University of Rosario, Argentina, and the University of Pittsburgh Medical Center was performed to identify patients who were reconstructed with a vascularized septal mucosal flap. Forty-three patients undergoing endonasal cranial base surgery were repaired with the septal mucosal flap. Two patients with postoperative cerebrospinal fluid leaks (5%) were successfully treated with focal fat grafts. We encountered no infectious or wound complications in this series of patients. One patient experienced a posterior nose bleed from the posterior nasal artery. This was controlled with electrocautery and the flap blood supply was preserved. The HBF is a versatile and reliable reconstructive technique for defects of the anterior, middle, clival, and parasellar skull base. Its use has resulted in a sharp decrease in the incidence of postoperative cerebrospinal fluid leaks after endonasal skull base surgery and is recommended for the reconstruction of large dural defects and when postoperative radiation therapy is anticipated.

Expanded endonasal approach: fully endoscopic, completely transnasal approach to the middle third of the clivus, petrous bone, middle cranial fossa, and infratemporal fossa

The middle third of the clivus and the region around the petrous internal carotid artery (ICA) is a difficult area of the skull base in terms of access. This is a deep area rich with critical neurovascular structures, which is often host to typical skull base diseases. Expanded endoscopic endonasal approaches offer a potential option for accessing this difficult region. The objective of this paper was to establish the clinical feasibility of gaining access to the paraclival space in the region of the middle third of the clivus, to provide a practical modular and clinically applicable classification, and to describe the relevant critical surgical anatomy for each module. The anatomical organization of the region around the petrous ICA, cavernous sinus, and middle clivus is presented, with approaches divided into zones. In an accompanying paper in this issue by Cavallo, et al., the anatomy of the pterygopalatine fossa is presented; this was observed through cadaveric dissection for which an expanded endonasal approach was used. In the current paper the authors translate the aforementioned anatomical study to provide a clinically applicable categorization of the endonasal approach to the region around the petrous ICA. A series of zones inferior and superior to the petrous ICA are described, with an illustrative case presented for each region. The expanded endonasal approach is a feasible approach to the middle third of the clivus, petrous ICA, cavernous sinus, and medial infratemporal fossa in cases in which the lesion is located centrally, with neurovascular structures displaced laterally.